The present invention relates to a device for the dispensing of fluid materials such as liquids, creams, gels and pastes under higher than atmospheric pressure. More particularly, the present invention relates to a device which is readily refillable by inserting a refill assembly into an outer casing for dispensing such cosmetics as perfumes, hairsprays, creams and lotions and also such materials as household cleaners and food materials.
In the development of the art, the pressure for dispensing such materials customarily has been supplied by incorporating in the container, along with the fluid material to be dispensed, a pressurized propellant such as a fluorocarbon aerosol whose vapor pressure was such as to force the liquid material from the container when a dispensing valve was opened. While these arrangements were and are operable, there are substantial objections to their use. In the first place, their use presents a serious environmental hazard since there is substantial evidence that the aerosol propellants are destructive of the ozone belt which protects the earth from harmful ultra violet rays. A second objection is that such aerosol dispenser is used only once and then discarded with the resultant waste of a container casing and valve which represents not only a waste of materials and energy but also a waste of money. The disposal of the discarded aerosol dispenser constitutes a major, expensive chore for society.
It is accordingly apparent that the above disadvantages could be avoided if the fluid material were placed in a refill assembly which would be readily inserted in a housing or outer case so that the fluid material might be dispensed by the application of an outside pressure which might be applied by a spring.
An object of the present invention is to provide an improved device for dispensing fluid material in the form of a spray, mist or stream under suitable pressure, said device being simple, inexpensive, rugged, economical of materials and readily refillable by the user.
The device of the invention comprises an outer cylindrical casing topped by a cover having therein an aerosol valve assembly; a disposable refill assembly including a rigid cylindrical sleeve and dimensioned to be readily insertable in and removable from said casing into and out of communication with said aerosol valve; a biased piston assembly adapted to be received in a lower portion of the rigid cylindrical sleeve and to bear against a lower end of a wiper seal, the wiper seal effectively sealing a fluid chamber of the refill assembly, and a bottom cover/cam adapted to be releasably secured to a lower end of the outer casing and, when so secured, so as to release the biased piston to urge the wiper seal upwardly to pressurize the fluid chamber. A locking means, for securing the piston to a lower sleeve closure of the cylindrical sleeve is provided by a bayonet lock arrangement including at least one locking detent slot in the lower closure of the cylindrical casing cooperating with at least one locking pin extending axially from the piston.
The entire biased piston refill assembly is secured in the outer casing by the bottom cover. The bottom cover is threaded onto the outer casing to secure the refill assembly in the outer casing while simultaneously releasing the piston from the lower sleeve closure.
The fluid is provided inside the rigid sleeve (or "liner" of the refill assembly) so as to facilitate insertion of the refill assembly into the container. The sleeve extends to the lower opening of the outer casing, when the bottom cap is off, so that the refill assembly can be reached for easy removal when the fluid product chamber is empty. The upper end of the sleeve is sealed by an upper sleeve closure and the product chamber is effectively sealed by the wiper seal to permit pressurization of the product chamber by the biased piston. The center of the upper sleeve closure contains an opening incorporating an annular deformable sealing member through which, when the stem of a metering valve is inserted, the product chamber communicates with the valve by sliding the same through the sealing member. In this way the contents of the product chamber are readily dispensed.
When the biased piston is released by rotational movement of the bottom cover/cam, the entire product chamber is pressurized. In this way, refilling the device is simplified.
To assemble the device, only a single refill assembly including product chamber, wiper seal, biased piston spring and releasable locking means is inserted in the outer case. The biased piston is readily released by securely threading the bottom cap onto the outer case. In this way, refilling the device is an easy procedure which does not involve physical contact or exposure with the fluid product.
At least one lock hook extends downwardly from the bottom of the biased plunger. The hook cooperates with at least one detent slot in the lower sleeve closure of the cylindrical sleeve.
The cam-cover is the last part to be assembled when refilling the dispensing device. It comprises a cap containing in the center a raised portion. When the cam-cover is substantially fully threaded on the outer case, the raised portion acts as a cam to release the piston and thereby pressurize the container. This also is a safety feature, for the piston is not readily releasable until the cam-cover is put into place and rotated.
The refill may, and preferably does, have an aluminum foil label seal over the opening in the center of the refill cover member, for shipping. This seal can be removed just prior to inserting the refill assembly into the outer casing, or the refill assembly may be inserted in the outer casing and urged against the valve with the seal intact, thereby permitting the valve stem to puncture the seal and at the same time sealing the refill to the valve by means of a sealing ring. Either way, the product inside the refill remains hermetically sealed until put into use. This is very useful for things such as medicines or chemicals that can be contaminated by prolonged exposure to air or sunlight.
The device of the present invention includes an outer case and an end cap which is threadably received by the outer case. A valve stem is provided in an upper end of the outer case. A refill assembly including a rigid cylindrical sleeve is receivable within the outer case and is securely positioned within the outer case by the bottom cap. The refill assembly includes an upper closure member which receives the valve stem of the outer case to permit the fluid contents of the refill assembly to be dispensed. A piston including at least one lock hook is slidably received within the rigid sleeve of the refill assembly. The piston is biased towards the upper closure of the rigid sleeve by a coil spring. A wiper seal which is preferably of a resilient material is provided immediately above the piston to effectively seal the product chamber of the refill assembly. The wiper seal includes an annular portion and an integrally joined disc portion. The at least one latch hook is releasably engaged in a lower closure portion of the cylindrical sleeve. The end cap includes an upwardly extending cam portion which releases the latch hook from the lower closure portion when the end cap is threaded onto the outer case. The end cap urges the refill assembly towards the valve stem so as to provide a communication between the product chamber and the valve. Simultaneuously, the end cap securely positions the refill assembly within the outer case and releases the biased piston to pressurize the product chamber.